Comets: the oldest inhabitants of the Solar system
J. L. Lagrange (1813) was also based on firmly established facts – the presence of comets that definitely move in elliptical orbits, including short-period. He explained the origin of comets gigantic volcanic explosions – emissions (eruption) with giant planets. It is, in principle, could explain the nature of the orbits of short-period comets. Subsequently, the views of La Grange shared and developed a number of scientists, among which the most important contribution of the Soviet astronomer S. K. Bo, who worked in this direction with the 20-ies to 80-ies of our century. He has eliminated the biggest internal difficulty is the concept of Lagrange – the necessity of the ejection of cometary masses (nuclei) with the “surface” of the giant planets with their powerful gravity fields, the overcoming of which requires an initial speed of 60 km/s and more. Giant planets also have thick (the length of many thousands of miles) and very dense atmosphere, in the middle of the twentieth century has been very problematic the very existence of a solid surface planets – giants beneath these atmospheres. Continue reading
In addition, comets can carry the names of the people who discovered them, e.g., comet Halley, comet Machholz, comet shoemaker–levy 9 comet or Mac Note.
Movement and spatial distribution
All comets are members of the Solar system. They, like the planets, are subject to the laws of gravity, but move very peculiar. All the planets revolve around the Sun in one direction (which is referred to as “direct” as opposed to “reverse”) on nearly circular orbits that lie roughly in one plane (the Ecliptic), while comets move in both forward and reverse directions on highly elongated (eccentric) orbits, inclined at different angles to the Ecliptic. It is the nature of motion immediately gives the comet.
Long-period comets (orbital period greater than 200 years) come from regions located thousands of times further than the most remote planets, and their orbits are tilted at all angles. Short-period comets (period less than 200 years) come from the region of the outer planets, moving in the forward direction for orbits lying close to the Ecliptic. Continue reading
The diversity of comets in the Solar system
The comet (from al-Greek. hairy, shaggy) – a small celestial body having a foggy view, orbiting the Sun in conic section with a very extended orbit. When approaching the Sun, the comet forms a coma and sometimes a tail of gas and dust.
Comets are placed into circulation periods:
At this time, found more than 400 short-period comets. Of these, about 200 were observed in more than one perihelion passage. Short-period comets (period less than 200 years) come from the region of the outer planets, moving in the forward direction for orbits lying close to the Ecliptic. Away from the Sun, comets usually do not have “tails”, but sometimes have a barely visible “to”, surrounding the core; together they are called the “head” of the comet. Approaching the Sun the head is increased and there is a tail. Many of them belong to so called family. For example, most of the short-period comets (full rotation around the Sun lasts 3-10 years) form the family of Jupiter. A little smaller of a family of Saturn, Uranus and Neptune (the latter, in particular, is the famous comet Halley). Continue reading